12(S)-HETE increases intracellular Ca(2+) in lymph-endothelial cells disrupting their barrier function in vitro; stabilization by clinical drugs impairing calcium supply

Cancer Lett. 2016 Sep 28;380(1):174-83. doi: 10.1016/j.canlet.2016.06.022. Epub 2016 Jul 4.

Abstract

Secretion of 12(S)-HETE by breast cancer emboli provokes "circular chemorepellent induced defects" (CCIDs) in the adjacent lymphatic vasculature facilitating their intravasation and lymph node metastasis which determines prognosis. Therefore, elucidating the mechanism of lymph endothelial cell (LEC) wall disintegration may provide cues for anti-metastatic intervention. The role of intracellular free Ca(2+) for CCID formation was investigated in LECs using MCF-7 or MDA-MB231 breast cancer cell spheroids in a three-dimensional cell co-culture model. 12(S)-HETE elevated the Ca(2+) level in LEC by activating PLC/IP3. Downstream, the Ca(2+)-calmodulin kinase MYLK contributed to the phosphorylation of Ser19-MLC2, LEC contraction and CCID formation. Approved clinical drugs, lidoflazine, ketotifen, epiandrosterone and cyclosporine, which reportedly disturb cellular calcium supply, inhibited 12(S)-HETE-induced Ca(2+) increase, Ser19-MLC2 phosphorylation and CCID formation. This treatment strategy may reduce spreading of breast cancer through lymphatics.

Keywords: 12(S)-HETE; Endothelial integrity disruption; Intracellular Ca(2+); MLC2; MYLK; PLC/IP(3).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid / pharmacology*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology*
  • Calcium / metabolism*
  • Calcium Channel Blockers / pharmacology
  • Calcium Chelating Agents / pharmacology
  • Calcium Signaling / drug effects*
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism
  • Cardiac Myosins / metabolism
  • Cell Movement*
  • Coculture Techniques
  • Dose-Response Relationship, Drug
  • Endothelial Cells / drug effects*
  • Endothelial Cells / metabolism
  • Female
  • Humans
  • Inositol 1,4,5-Trisphosphate / metabolism
  • Lymphatic Metastasis
  • Lymphatic Vessels / drug effects*
  • Lymphatic Vessels / metabolism
  • MCF-7 Cells
  • Myosin Light Chains / metabolism
  • Myosin-Light-Chain Kinase / genetics
  • Myosin-Light-Chain Kinase / metabolism
  • Permeability
  • Phosphorylation
  • RNA Interference
  • Serine
  • Spheroids, Cellular
  • Time Factors
  • Transfection
  • Type C Phospholipases / metabolism

Substances

  • Calcium Channel Blockers
  • Calcium Chelating Agents
  • Calcium-Binding Proteins
  • Myosin Light Chains
  • myosin light chain 2
  • Serine
  • 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid
  • Inositol 1,4,5-Trisphosphate
  • MYLK protein, human
  • Myosin-Light-Chain Kinase
  • Type C Phospholipases
  • Cardiac Myosins
  • Calcium